Belt shifting mechanism



June 2s, '1949.

M. L. DODGE BELT SHIFTING MECHANISM 5 Sheets-Sheet l Filed NOV. 30, 1946 /m/ENaa MER-MN L. DODGE .4T70BNEYJ June 28, 1949. M. L DODGE 2,474,470

BELT SHIFTING MEGHANISM Filed Nov. 30, V1946 5 Sheets-Sheet 2 mu/v70@ M15/@TON L. DODGE HTTOENE Y June 2s, 1949. M. L, DODGE 2,474,470-

BELT SHIFTING MECHANISM Filed Nov. 30, 1946 y 5 Sheets-Sheet 3 .3@ if "ILL-:113i n E INVENTOR.

NE/ZTON Dgo GE June 28, 1949. M. L. DODGE 2,474,470

BELT SHIFTING MECHANISM Filed Nov. 30, 1946 5 Sheets-Sheet 4 l INVENTOR. Meere/v L DODGE HTTOENEYJ June 28, 1949. M. Il.. DODGE 2,474,470

BELT SHIFTING MECHANISM Filed Nov. 3o, 194e; 5 sheetysneet 5 NN Q10.

firme/vf YJ Patented June Z8, 1949 .BELT SHIFTINGMEGHANISM- Merton L. Dodge, seattle, tva-sli.V application November 3o, 1194s,:seria1z`No; 713,222-

.5 Claims. (Cl. #f1-7242.3)

This invention relates :to beltnshifting mechanisms and it has :reference more particularlyto improvements sin' means. for Ithe. shifting of a -Vbelt where such-belt-iszused in connection with a pair ofstepped pulleys andzis shifted for -the purpose of changing-the speed'and power ratios between the .shafts on :which'the `'pulleys are mounted. For example, the invention. may be embodied vvin a mechanism' for use.` in lconnection .with'complementalorpaired, stepped pulleys as used on adrivingshaftand on the driven shaft of a turning lathe .or fthe like. :Itis notithe intent, however, I-that -thefinvention be vlimited in itsvuse either to anygparticular machine kor :even

`to V-belts.

It is the principal object of .this invention to provide `a comparatively vsimple, manually operable mechanism whereby a V-belt may be .easily and quickly disengaged vfrom the-pulleys, shifted and selectively applied by belt carrier housings to any of the paired sets of grooves of the 'complemental stepped pulleys. Furthermore, it is aan object-of the invention to effect such an voperation of releasing tthe belt, vshifting and/selectively applying it to the Agrooves of the pulleys, through the mediacy of a singlecontrol element.

Another objectof my .invention .is to provide-a belt shifting meansithat .maybe easilyfassociated with presentday belt slackening means as used in connection with 'V-belt drive pulleys.

It is a further object .of the invention, ,tolprovide an indexing `means in'associationy with the single control' element for accurately determining the position of thebelt carrier `housings,after thebelt has been disengaged vfrom the pulleys, for the application of lthe belt thereby -to any selected pair of pulley fgrooves.

Other` objects of the invention are to be found I in the details Vof construction of parts; in the combination and relationship of parts and in the mode of operation and use of -the mechanism vfor its intended purposes, as -willhereinafter be fully described.

-In accomplishing these and other objects of the invention, I have provided the improveddetails of construction, the preferred forms of which are illustrated in the accompanying drawings, wherein- Fig. 1 is a vertical cross-'section of a machine equipped -with a V-beltshifting'mechanism em- -i bodied by thepresent invention.

Fig. 2 is a horizontal section ofthe same, taken substantially on `the line 2-'2 in Fig. 1, showing the shifting mechanism in plan view.

Fig. 3 is a'somewhatenlargediront elevation of parts of the machineLshown in.Fig.`2.

Fig. 4 is an enlarged, vertical section taken on the lined- 4 in 'Figs.1.and"5.

Fig. 5 is .a cross-sectiontakenon :line5-5 in Fietl. v

f2 ,-Fig. "6 is :anwenlargeds vertical section taken --substantiallyaondine;6&6 in Fig.2. y

It ia" commoneiarrangement `of A:parts Y in AIna- .chines employing fsteppedmulleys fand V-be1tsf,to :mount onefofthexsteppedfpulleys cna-shaft that has a swinging support and means associated with'l the ff sunpilrt for Aadjusting it yto Vprovide the necessary. yslack fin Ltheidriving Ybelt `to 'permit rits -fdisengagenentjrrom `onelpalirofy Apulley -grooves fand-its applioationtoianotherpair. 1 However, vto .my knowledge, noefmeansaha's .heretofore -been .provided "whereby theibelt could be `mechanically Vpicked up, :shifted andy-.selectively fapplied to any .-pairl orsetofgroovesfin `.theoomplemental pulleys. ,"fherefre, it isV .onlyito .tlie..provision Nof Asuch a Vmechanism .and L its novelacombination with lthe Y usually yu'sedbl't.slacleningland tightening means that `thei`p1esent in'vention relates xand 4to which .claims will-be" iriade..lffl1?lie..particular type of "machine showninfthe .drawings A.has been -selected onli'7 :fas ameansloillustrating a .typical .application of theli'mechanism 'ofthe .invention and the lmode o'f operation f ithefmechanism.

' "Referring more in detailflt'the"drawings- 'nFigs.'larid'ffl.designates what may be the bencliorplate on "ich;a"lathe,l.or similar type fmalchiriefismbuft'e alld'i sigha'ts ahOri- 'zontal' shait .which inight"be'the.spindle ,of the `lathe-and""o'nwhich `S'lildlen driyinglpulley wheel ji 2' fis mounten; "pisse, wattacheo to'iine bench Hla'tftsV 'undersiegfis a .horizontally .disposed frame"structure'Jiif` T=shape inlplang as seen in Fig;Y 2 g 'anfdesignateu gnerauyinnigs. 1, l2 and -6n byhmneralv I'SIfThe'frame il 3 'is shown in Figs. "1' andf2 asbeingadjustablyfxed to 'the 'bench -ii'u througntnenneia 'y' of "tnreeboiis .designated four Isepairate' steps'lof graduallyiincreaseddiamedrive shaft designated by reference numeral and it is shown best in Fig. 4 as being located below and parallel to the shaft I4 and to be rotatably contained in an elongated sleeve bushing 26 that is mounted in a cross bearing 2l that is formed at the forward end of a swing frame 28.

The swing frame is shown in Fig. l as being pivotally supported between its ends by aA horizontal, pivot shaft 29 that is mounted by and extended between two spaced legs 30 and 30 .that extend downwardly and rearwardly from the cross head portion of the frame I3 previously mentioned.

At its rearward end, as shown best in Figs. l and 2, the swing frame 28 mounts an electric motor thereon and a V-belt 36 extends about a V-belt pulley 3l on the drive shaft 35' of the motor and about a larger pulley wheel 38 that is mounted on and keyed to one end of the shaft 25; this latter belt being under driving tension at all times.

Keyed on that end of the shaft 25 that is opposite the end carrying the driving pulley wheel 38, is a stepped pulley wheel 4U that is paired with and is the complement of the stepped pulley wheel 25 on the driven shaft I4. A driving connection between the pulleys 4o and 20 is provided through the mediacy of a V-belt 4l and the mechanism embodied by this invention is for the purpose of releasing, supporting, and shifting this belt and for selectively applying it to any of the pairs of grooves in the complemental pulleys. The shifting mechanism which I have provided is used in conjunction with the swing frame 23 and its actuating toggle and both the shifting mechanism and the toggle are under control of a common operating member.

t is to be understood that before the V-belt 4l can be shifted along its pulleys from one pair of grooves to another, it must first be slackened and disengaged from the pulley grooves, and that after an adjustment to a selected pair of grooves has been made, it must be seated therein and again be drawn taut. VThis slackening and tightening of the belt 4l is herein accomplished by the swinging of the forward end of the ,frame 2S, toward and from the driven shaft I4. For accomplishing this swinging action, I provide a toggle linkage which, as shown in Fig. 6, comprises a bell crank lever 45,' mounted pivotally on a horizontal shaft 4B that is xedly supported at its ends in spaced parallel webs l3a: formed aloner the under side of the stem portion of the T- shaped frame I3, as shown best in Fig. 6.

It is shown in Fig. 6 that the bell crank lever has an arm 45a that extends downwardly and rearwardly and at its lower end has a bolt 41 adjustably mounted therein as an extension of the arm. At its outer end, the bolt is pivotally attached by a pivot member 48, to a link 49 which, in turn, is connected pivotally by bolt 5U with the forward end portion of the swing frame 28. The other arm, 45h, of the bell crank lever 45, extends upwardly and rearwardly and at its end is operatively connected with devices later described for actuating it forwardly and rearwardly, thus to elfect the raising and lowering of the forward end of the swing frame for the purpose of slackening and tightening the belt 4 I, as applied to the stepped pulleys 20 and 40.

When the center pointof the pivotal connector '48 in the toggle linkage passes forward, slightly past a dead center line between the pivot axes 46 and 55, the upper arm 45h of the bell crank lever will engage with a stop member 52 in the frame I3 and thus the linkage will be locked against belt slackening action except by a reverse action effected through a forward pull in the upper arm of the bell crank.

The present belt shifting mechanism takes into consideration the provision for slackening and disengaging the belt 4l from both pulleys, the moving of the belt bodily to positions for application to the selected set of grooves and finally the readjustment of the swing frame to cause the drive pulley to engage the belt and thereby cause it to be drawn from the housings and seated in the selected pair of grooves.

The mechanism for this purpose comprises upper and lower belt-guide housings which are best shown in Figs. 1, 4 and 5. The upper beltguide housing is'designated by numeral 55 and it comprises an inverted U-shaped member of channel form, with the channel facing inwardly. This housing is of such size as to permit it to be registered with and about the step of greatest diameter of pulley wheel 20 as shown in Figs. 4 and 5. Also, this housing 55 is xed rigidly to a supporting frame 56 that has bearings 55-5G longitudinally slidable on the opposite end portions of the sleeve l5 in which shaft I4 is rotatably contained. The movement of this frame 56 along the sleeve in opposite directions is such that the U-shaped housing may be brought selectively into alignment with any one of the pulley grooves or steps of the pulley 20.

The lower belt guide housing comprises a U- shaped housing B that is like, and is the complement of the guide housing 55, and this is of such size that it may be registered about the largest step of the driving pulley wheel 4Q. Likewise, this lower belt guide housing GQ is supported by a frame 62 having a bearing portion 62 that is mounted on and is slidable along the adjacent end portion of the sleeve 26 in which shaft 25 is rotatably contained. Also, it is shown in Figs. 4 and 5, that the bearing 62 is equipped at opposite sides of the shaft 25 with vertically bored holes 64-54 and that parallel rods 65 and 65 are xed at their upper ends in the frame bearing 56' of the upper guide housing and have their lower end portions slidably contained in the holes l[i4- 64 so that the two housings will be held in proper alignment with the moving of the shaft 25 toward and from the shaft I4 for the belt slackening and tightening operations as accomplished through the actuation of the toggle link-age.

It is to be explained that the two guide housings are at all times, except 'when shifting the belt, aligned with the pulley grooves in which the belt 4l is contained, and that whenever the swing frame 28 is actuated upwardly to slacken off this belt preparatory to shifting it, the lower guide housing moves upwardly with the lower pulley wheel, as from the dotted line position to the full line position in Fig. 5, and thus the belt 4l is caused to be picked up first in the channel of the lower housing and shifted upwardly and into the channel of the upper housing as has been shown clearly inFig. 5. Then, by shifting the housingsin the axial direction along the pulleys, the'belt may be` brought into registering alignment with any selected pair of grooves in the complemental pulleys. After thus being brought into registration with the selected grooves, to seat it, it is only necessary` to actuate the swing frame downwardly thus to swing the lower pulley wheel 40 back to its lowered position. In this downward swing of the pulley 4Q, it engages the lower end loop of the belt 4I and f' the lbelt is #therebylr-f draw 1 --lateral 5 shifting of :the

dow

from or intoztneibeil'reran arrrrfasa.

The-means which disposed againsttheY-ffrontl face-f of: fplate'-Vv "I 5; At its inner end; .ther tubularsupport' IS-has aV crank v `arm 80 fixed ltheretog-fillandra llinkl '8|' fpivotally AThe 'rotatableadjustment''ofE the Igear-shousing 'i9 and' its supporting?member''lSpffor this above purpose',V` is ehereinilaccomplished ithrough the mediacy of alever'arm 84 which is shown in Fig. 3 as having a bifurcated end providing arms 85-85 that-extend'to-opposite*sides of the hous- -ing |9- and are--there-securedonopposite ends of a shaft 86 that extends rotatably fand directly through the housing 19. The swinging of this lever 84 aboutithefaxial'lineof--support 'I8 full line position in Fig. 3-to---the successivedotted line positions, causes,the-belt-guide housings to .be shifted successively into registration with the different sets of grooves of the stepped pulleys and 49.

To determine the exact position of the belt guide housings for the seating of the belt 4| in a selected set of pulley grooves, I have provided the face plate 15 with a series of sockets 81 located in an arcuately curved line that is formed about the mounting axis of the housing as a center, and I have mounted a spring pressed ball 81' in a socket 88 in the housing wall as noted in Fig. 6, that will be successively seated in each of the sockets 81 as the housing is turned through its arc of movement by the lever 84. This seating of the ball will determine the stopping point and will yieldingly retain the housing in a set position.

In order that the lever 84 may also be used as the means for the actuations of the swing frame 28 to slacken olf and also to tighten the belt 4|, I have mounted a rack bar 90 for longitudinal movement in the tubular support 1B, as shown in Fig. 6. This rack extends inwardly from the bearing 78 and at its inner end has a block 9| swivally xed thereon. The block, in turn, is connected to the outer end of the upper arm 45h of the bell crank by a pair of links 92 which have pivotal connection at their ends respectively, with the block and lever arms, as at 93 and 94. Keyed on the mounting shaft 86 of the lever arm 84 within the housing 19, is a gear wheel 9'5v and this is in operating mesh with the rack bar 90. Thus, by the swinging of the lever arm, as from its full line to the dotted line showing in Fig. 6, the rack bar will be shifted outwardly, and the swing frame 28 moved upwardly, thus to slacken the belt 4| and cause it to be disposed in the belt guide housings and clear` of the pulleys as in Fig. 5. After this has been done, the upwardly ex- 1ide orthe fother, totthusil'ocate` thefibeltin :proper position fior its .tapplicationvto afse'le'cted'pairV of *'-groovesl in l/ the 'pulley wheels.' 1^ ."Finally, the `lever vfis swung back toi its. lower fliinit, as 'to one-of.` the lp'ositionsindicated'k 1in` Fig. v6,2 thus ,tof reseat the vbeltfand vdraw itftight in the pulley grooveswhere itis functionallyiheldfby: the toggle linkagef-until f '-man'ually releasedrf or readijustm'ent.

By thisvmeans Aabove -.d'escribed, I have` provided '-"fortherelea'sing of the'b'elt f4'lffrom its pulleys, =for` its. shiftingand` its` reeapplication to'uthe pulleys; by. thel'actuation' of; :thesingle ,memberll -Such amechanismim'ay be used iiflikeamanner forshiftingl of. flat belts'v used' linrconnection .with ordinary types ofpulleys.

f Having'.v thus f described' my; invention ,twhat I f'claim as new -thereinf fand` desire 1to1 secureliby Letters Patent. is:

' 1. lThe 'combinationviitn a-paircin-parallel shafts, V-belt pulleysmountedr ini/alignment thereon, eachhavi-ng a plurality of Velbelt 'grooves therein, a V''belt. applied!.abc'utttl'iel pulleys `and selectively 'applicable'to 1pairedr grooves-'thereof to'eiect a' driving connection, aiemovableframe l supporting onel of the 'shafts; .meansxfor L moving said frame to move.thefcorresponding.lpulley toward the other pulley.' toleffectL-thefdisengagement ofthe-'belt-from thepulley grooves, albelt Ihousing mounted 'formovementiwith the movable automatic seatingo'f therbeltfthereirrwheni'the pulleys are moved apart to a belt tightening relationship and a hand lever operable both for the actuation of the movable frame-adjusting means and for the shifting of the belt housing along the pulley shaft.

2. In combination, a pair of parallel shafts; one having a fixed support and the other having a movable support, complemental, stepped pulleys on said shafts and formed with a plurality of paired belt grooves, a belt operable about the complemental pulleys and selectively applicable to the paired grooves to effect a driving connection between the shafts, means for adjusting said movable support to disengage the bel-t from the pulleys, a belt housing supported by each shaft, and movable therealong, each housing partially enclosing the adjacent pulley and adapted, when the pulleys are adjusted to belt disengaging relationship, to receive the end loop portions of the belt therein and to support the belt in the clear of both pulleys and means for shifting the housings along the supporting shafts to locate the belt, as contained therein, in alignment with any of the paired grooves of the pulleys for seating therein incident to the return of the pulleys to itheir normal driving relationship; each belt guide housing having a supporting bearing receiving the corresponding supporting shaft therethrough for their relative rotative and longitudinal movement, one of said bearings having a bore formed therein in a plane that is perpendicular to the axial .line of the shaft and the support for the other housing having a rod xed therein and slidably contained in said bore to maintain the alignment of the housings during their adjustment and shifting of the belt.

3. In combination, a pair of parallel shafts, V-belt pulleys mounted thereon, each having a plurality of V-belt grooves, a V-belt applied about the pulleys and selectively applicable to paired grooves therein to effect the driving connection, a swing frame supporting one of the shafts for its movement toward the other to effect the disengagement of the belt from the pulleys, belt housings supported by the shafts and partially about the pulleys and movable from and toward each other with like movements of the shaf-ts, and adapted to receive the corresponding end loops of the belt therein when it is disengaged from the pulleys, means for shifting the belt housings along the shafts to align the belt, as carried therein, with any selected pair of grooves of the pulleys, a rotatably mounted housing, bar longitudinally movable therein, means operatively connecting the said rotatable housing with the belt guide housings whereby they will be shifted along the pulleys in accordance with its rotative adjustment, means connecting the said bar with the swing frame for effecting a relative adjustment of the pulleys incident to an endwise adjustment of the bar and a hand lever attached to the said rotatably mounted housing whereby it may be rotatably adjusted, and having an operating connection With the said bar for its longitudinal adjustment, independent of any rotative movement of the housing.

4. The combination with a pair of parallel shafts, stepped V-belt pulleys mounted thereon, a V-belt applied about the pulleys to provide a driving connection between them and a swine frame supporting one of the shafts for movement from and toward the other; of belt housings mounted on the shafts and partly about the pulleys for movement from and toward each other with the adjustment of the shafts and movable along the pulleys, and each having a groove adapted to receive the belt therein when disengaged from the pulley grooves, a fixed face plate, a gear housing rotatably mounted thereby, a rack` bar mounted for endwise movement in the hous ing and coaxially of its axis of rotation, means operatively connecting the bar with the swing frame for its actuation by an endwise movement of the bar, means operatively connecting the gear housing with the belt housings for shifting them along the shafts, by a rotative adjustment of the gear housing, a lever xed to the housing for rotating it and a gear on the shaft meshing with the rack bar for effecting its endwise movement, a shaft rotatably mounted in the gear housing, a gear fixed on said shaft in mesh with the racl; bar, and a lever arm fixed to said shaft for effecting its rotative adjustment and for the rotation adjustment of the gear housing each indepenfl ently of the other.

5. A combination as in claim 4 wherein a yieldM able latch element is mounted by the gear housing, and stops are arranged on said face plate corresponding to the steps of the pulleys, and in position to be engaged by the latch, each being adapted te locate the belt guide housings in alignment with corresponding steps of the pulleys.

MERTON L. DODGE.

REFERENCES CITED UNITED STATES PATENTS Name Date Faltermayer Mar. 5, 1940 Number 

